Fire Extinguisher Classes for FDNY COF Exams

Portable fire extinguishers come up in nearly every FDNY Certificate of Fitness study booklet we cover: the F-01, F-02, F-03/F-04, F-60, S-95 and C-14. Most of the material is shared, but each booklet adds its own details. This guide gathers it in one place and notes which booklet each point comes from. It explains the study material only; what your site needs is for your employer and the FDNY.

The five classes of fire

The booklets sort extinguishers by the class of fire they are meant for. The S-95 booklet notes that NFPA Standard 10 requires extinguishers to be chosen for the classes of fire hazard they protect.

Class	What burns	What the booklets say about putting it out	Symbol (F-02 booklet)
A	Ordinary combustibles: wood, paper, cloth, many plastics	The heat-absorbing effect of water or the coating effect of certain dry chemicals	Triangle, green
B	Flammable and combustible liquids and gases: oil, gasoline and similar	Smothering, oxygen-excluding agents such as CO2, dry chemical or foam	Square, red
C	Energized (live) electrical equipment	An agent that does not conduct electricity; no water or foam. Once the power is off, A or B extinguishers may be used	Circle, blue
D	Combustible metals such as magnesium, titanium and sodium	An agent that does not react with the burning metal; water should not be used	Five-point star, yellow
K	Cooking oils and fats in cooking appliances	Extinguishers listed for Class K; the F-02 booklet describes them working by saponification, forming a soapy foam on the oil	Letter K

The F-01, F-60 and F-03/F-04 booklets present Classes A to D in nearly the same words, and the F-03/F-04 booklet adds Class K for commercial kitchens such as restaurants, cafeterias and caterers. The booklets also say a multi-purpose dry chemical extinguisher can be used on more than one class of fire.

Common extinguisher types (F-02 booklet)

The F-02 shelter booklet goes further than the others and describes the extinguishers you are likely to see:

• ABC: the most commonly sold type, often the main extinguisher in shelters. Dry chemical, usually red, 5 to 20 lbs, usable on ordinary combustibles, flammable liquids and electrical equipment.
• Class A (air-pressurized water, APW): less common than ABC, usually silver, roughly 3 feet tall and about 25 lbs. For ordinary combustibles only.
• BC: for flammable liquid and electrical fires, filled with sodium or potassium bicarbonate. The booklet notes that extinguishers rated only "B" or only "C" do not exist; the "C" just means the agent does not conduct electricity, so it is always paired with a B or AB rating.
• Class K: found in kitchens, with wet or dry agents. The booklet warns the agent can sometimes conduct electricity, so it should only be used after the appliance's power is off.

Ratings and symbols

Extinguishers carry a rating such as 3-A:40-B:C or 10-B:C, which the F-01 booklet shows as examples. The booklets explain the picture labels too: a symbol with a shaded background and a slash through it means the extinguisher must not be used on that class of fire. The F-01, F-60, F-03/F-04 and C-14 booklets all say the holder must know or understand these symbols.

What each booklet adds

F-60: hot work and gas fires

The torch operations booklet sets a minimum: at least one extinguisher rated 2-A:20-B:C within 30 feet of the hot work and of where fire guards are posted, or a minimum 3-A:40-B:C for torch-applied roofing. It also covers gas fires from a leak: shut off the gas supply first and call 911, approach from upwind, and aim a dry chemical stream where the flame begins rather than at the middle of the flame. If the gas cannot be shut off and the supply is limited, such as a cylinder, the booklet says to let the flame burn out, call 911, and keep the fire from spreading. The F-60 and F-03/F-04 booklets also mention separate FDNY outdoor extinguisher tags for extinguishers placed outdoors.

F-02: placement in shelters

The F-02 booklet gives a weight rule: extinguishers of 40 lbs or less are mounted with the top no higher than 5 feet, and hand-held extinguishers over 40 lbs with the top no higher than 3.5 feet. Extinguishers go in conspicuous, readily accessible spots along normal paths of travel. It also says an extinguisher should only be used when there is a way out that is clear of fire.

C-14: chemical laboratories

The lab booklet says every laboratory and storage area must have extinguishers, generally dry chemical, and that all labs need at least a 20-B rating within a 50-foot travel distance. It flags lab-specific cautions: CO₂ and dry chemical are likely to be ineffective on oxidizer-based fires; for metal or pyrophoric fires, do not use water, foam or CO₂, only Class D extinguishers; and do not use an ammonium-based dry chemical extinguisher on chlorine-based oxidizers.

S-95: where extinguishers are required

The fire alarm booklet lists where portable extinguishers are required, including many occupancy groups, within 30 feet of commercial cooking equipment, areas with flammable or combustible liquids in quantities needing a permit, and each floor of a building under construction, alteration or demolition (with an exception for detached Group R-3 occupancies).

Using an extinguisher: P.A.S.S.

The F-01, F-02, F-03/F-04 and F-60 booklets all teach the acronym P.A.S.S., and the F-02 booklet spells it out:

1. Pull the pin from the handle.
2. Aim the nozzle at the base of the fire.
3. Squeeze the lever.
4. Sweep the nozzle from side to side until the extinguisher is empty.

The booklets also repeat: call 911 for any fire. Follow the instructions printed on the side of the extinguisher. Portable extinguishers are for small fires, not large or spreading ones, which are left to the building's fire extinguishing systems or to firefighters. And once an extinguisher has been discharged, a fully charged replacement is needed (the F-01 and F-60 booklets say before work restarts; the F-02 booklet says it must be recharged or replaced before it is used again). The F-01 and F-02 orientation checklists add that if no extinguishers are provided in your area, you carry one with you.

Mounting height

The F-01, F-60, F-03/F-04 and C-14 booklets give the same placement rule: the top of the extinguisher no more than 5 feet above the floor, the bottom at least 4 inches above it, and never on the floor. Remember the F-02 booklet's lower 3.5-foot limit for hand-held units over 40 lbs.

PFE tags

Every booklet we cover includes a section on the FDNY standard portable fire extinguisher (PFE) tag. The key points:

• Installed extinguishers must carry the FDNY standard PFE tag; since November 15, 2019 only the new tags are recognized, and the FDNY issues violations for extinguishers without a proper tag.
• Tag colors and year change every few years for security.
• Two ways to check a tag is genuine: a real hologram strip 3 inches long by ¼ inch wide, high-quality silver, that changes color as you move it against the light; and a QR code that leads to the FDNY's approved extinguisher company list.
• If a tag cannot be verified, tell your supervisor; suspected counterfeits are reported to the FDNY by email.

Inspections: monthly and annual

When	Who	What
Monthly ("quick check")	A person chosen by the owner (the C-14 booklet notes it may or may not be the C-14 holder)	Fully charged; in its designated place; not actuated or tampered with; no obvious damage or condition that would prevent operation. Record the date and the inspector's name or initials on the back of the tag or by an approved electronic method.
At least annually	A W-96 Certificate of Fitness holder from an FDNY-approved company	Inspects the extinguisher and replaces the PFE tag, recording the annual inspection on the new tag.

Lithium-ion batteries

Several booklets, including the F-01, S-95 and C-14, now end with a lithium-ion battery section. It states that fire extinguishers do not work on lithium-ion battery fires, that water may not stop a battery from burning, and that these batteries can reignite minutes, hours or even days later.

Try an example question

This question is our own, written from the booklets' content. It is not from a real exam.

An electrical panel is on fire and the power cannot be shut off. Which extinguisher do the booklets point to?

1. Air-pressurized water (Class A)
2. An extinguisher rated for Class C, such as BC or ABC
3. A foam extinguisher
4. Any extinguisher, as long as you use P.A.S.S.

Answer: B. The booklets say live electrical fires need a nonconductive agent and that water and foam must not be used. A or B extinguishers are only an option once the equipment is de-energized.

Practice the extinguisher questions

Practice the bank for your exam: start with the free questions on the F-01, F-02, F-03/F-04, F-60, S-95 or C-14 page. Full banks and timed mock exams are on the pricing page.